Applying Hubbert Curves and Linearization to Rock Phosphate

Rock phosphate is a critical, nonrenewable resource for which there is no known substitute in agriculture. Cordell, Drangert, and White (2009) use Hubbert methodology (1956) to estimate the peak--the year after which production will monotonically decline--of world rock phosphate production at 2033-34. This note assesses the applicability of Hubbert’s (1949) peak methodology to world rock phosphate production, based on (a) the ability of the model to produce accurate in-sample and out-of-sample forecasts and stable estimates of ultimately recoverable reserves, and (b) the degree to which the rock phosphate market approximates the theoretical conditions underpinning the Hubbert model. In both respects, the application of Hubbert methodology to rock phosphate is found to be problematic.peak phosphate, Hubbert curves, Hubbert linearization, rock phosphate

Markets vs. Malthus: Food Security and the Global Economy

In the past four years, rising world food prices and the global economic downturn increased the ranks of the world’s food insecure from 848 million to 925 million by September 2010, reversing decades of slow yet steady progress in reducing hunger. While the human costs have been considerable, the political consequences have been significant as well, fueling concerns of two skeptical groups, Neo-Malthusians and food sovereignty advocates. Hendrix assesses the claims of both. On the Neo-Malthusian position, he finds that while population growth and economic development contribute somewhat to price increases, there are few structural, resource-based impediments to increasing aggregate agricultural production. The biggest near-term threats to food security are not dwindling agricultural inputs and agricultural trade, but rather the familiar problems of poverty and political barriers to market access—in particular, the distortions created by agricultural policy in the United States and European Union. A robust trading system is the best way to address current food security problems. In light of forecast changes in global patterns of agricultural productivity, a robust trading system will become even more important to ensuring that a world undergoing climate change will be able to feed itself.

Graviton-photon conversion on spin 0 and 1/2 particles

The differential cross-sections for scattering of gravitons into photons on bosons and fermions are calculated in linearized quantum gravity. They are found to be strongly peaked in the forward direction and become constant at high energies. Numerically, they are very small as expected for such gravitational interactions.Comment: 13 pages, LaTeX with 5 figure

The characterisation of armed conflict and targeted killing of suspected terrorists under international humanitarian law: reflections on the future of Jus in Bello

The use of drones for the targeted killing of suspected terrorists has raised a number of complex legal issues for scholars and practitioners in field of international law. This paper will focus on the applicability of international humanitarian law in such situations and the characterisation of drone warfare as armed conflict. In this context, the scope of armed conflict as a concept of international humanitarian law will be explored. In doing so, emphasis will be placed on the need for accountability to ensure greater compliance with international law

A New Low-Mass Eclipsing Binary from SDSS-II

We present observations of a new low-mass double-lined eclipsing binary system discovered using repeat observations of the celestial equator from the Sloan Digital Sky Survey II. Using near-infrared photometry and optical spectroscopy we have measured the properties of this short-period [P=0.407037(14) d] system and its two components. We find the following parameters for the two components: M_1=0.272+/-0.020 M_sun, R_1=0.268+/-0.010 R_sun, M_2=0.240+/-0.022 M_sun, R_2=0.248+/-0.0090 R_sun, T_1=3320+/-130 K, T_2=3300+/-130 K. The masses and radii of the two components of this system agree well with theoretical expectations based on models of low-mass stars, within the admittedly large errors. Future synoptic surveys like Pan-STARRS and LSST will produce a wealth of information about low-mass eclipsing systems and should make it possible, with an increased reliance on follow-up observations, to detect many systems with low-mass and sub-stellar companions. With the large numbers of objects for which these surveys will produce high-quality photometry, we suggest that it becomes possible to identify such systems even with sparse time sampling and a relatively small number of individual observations.Comment: 15 Pages, 9 Figures, 6 Tables. Replaced with version accepted to Ap

James Barron Hope : Virginia\u27s Poet-Laureate

Previous to the Civil War comparatively little literary work had been done in the south. Of course if we take into consideration all kinds of composition, such as narratives of adventure, diaries, histories, speeches, sermons and the like, we are forced to admit that the total amount was very large. But when we speak of literature in the higher and more restricted sense, we mean that which stimulates the imagination, awakens thought and aims to please as well as to instruct. And, using the word in this narrow and more restricted sense, it is quite evident that there had been quite a scarcity of literature in the south. In the realm of southern poetry, unquestionably the three greatest names since 1865 are Sidney Lanier of Georgia, Paul Hamilton Hayne of South Carolina, and James Barron Hope of Virginia. The last-named of this illustrious trio is selected as the subject of this paper

Parasitic Uterine Myomata.

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